feat: Enhance Stock Ledger functionality with item details and filters

- Updated StockService to compute running balance on read and include item SKU, name, category, and brand in StockLedgerRowDto.
- Modified GetLedgerAsync method to accept categoryId and brandId parameters for filtering.
- Enhanced StockController to support new query parameters for ledger retrieval.
- Updated StockDtos to include additional item information in StockLedgerRowDto.
- Adjusted frontend Stock Ledger page to display item details and implement searchable item picker.
- Added tests for StockLedger to verify running balance calculations and filtering by category and brand.
- Updated appsettings for service URLs and modified login page navigation logic.

Backend/ERPCore/Dtos/Stock/StockDtos.cs

@@ -11,7 +11,8 @@ public sealed record StockOnHandDto(
 public sealed record StockLedgerRowDto(
     int LedgerId, int ItemId, int WarehouseId, int? BinId, int? BatchId, int? SerialId,
     Direction Direction, decimal QtyBase, decimal UnitCost, decimal Value, decimal RunningBalance,
-    string SourceDocType, int SourceDocId, int UserId, DateTime CreatedAt);
+    string SourceDocType, int SourceDocId, int UserId, DateTime CreatedAt,
+    string? ItemSku = null, string? ItemName = null, string? CategoryName = null, string? BrandName = null);
 
 /// <summary>An open FIFO layer in a valuation (docs/11 §5.3).</summary>
 public sealed record StockValuationLayerDto(int LayerId, decimal QtyRemaining, decimal UnitCost, decimal Value, DateTime ReceiptDate);